A semiconductor power device usually generates substantial amount of heat at and near its active region. Usually, a maximum temperature, often referred to as the maximum junction temperature, is specified at which the temperature of the active region should not exceed so that the semiconductor power device may be operated in a safe and reliable manner.
Generally, the semiconductor material used in the semiconductor power device are optimized for processing signals at high frequencies, such as radio frequency (RF), microwave, and millimeter wave, but not necessarily optimized to remove heat from the active region of the semiconductor power device. Accordingly, the effective thermal impedance through such semiconductor material is generally undesirably high.
Thus, there is a need to decrease the effective thermal impedance to reduce the temperature of the active region or allow the semiconductor power device to operate at higher power configurations.